"Rush" is an electrifying club-pop anthem that celebrates recreational drug-fueled early morning dance parties. It is a tribute to the wild nights Troye Sivan spent partying on Melbourne's Smith Street, mending his heartache. With sultry vibes, it evokes a massive crowd embracing acceptance and sexual liberation. "'Rush' is the feeling of kissing a sweaty stranger on a dance-floor, a two-hour date that turned into a weekend, a crush, a winter, a summer," explained Sivan. "Party after party, after party after party. All of my experiences from a chapter where I feel confident, free and liberated," he added. "Independent, yet somehow the most connected to the music and community around me."

The title nods to "Rush," a brand of poppers widely embraced by gay men for their euphoric effects. The intoxicant helps them to relax during their sexual encounters.

Sivan wrote the song with Alex Chapman and Leland, and the track's producers Zhone, Novodor and Stylaz Fuego. Mississippi-born songwriter Brett Leland McLaughlin is Sivan's go-to songwriting partner. Their other collaborations include "Youth," "My My My!" and "Dance To This." Kaelyn Behr, also known by his stage name Styalz Fuego, is a songwriter and record producer based in the United States. He previously worked with Sivan on the Knocks remix for his collaboration with Charli XCX, "1999," and his single with Regard and Tate McRae, "You."